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arXiv · 2605.21290

Serre functors and local duality for affine quotients

Ivan Noden
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Abstract

The purpose of this short note is to study Serre functors of categories of quasicoherent sheaves on stacks of the form $\mathcal{Y} = \mathrm{Spec} A/G$ where $G$ is a reductive group acting on $\mathrm{Spec} A$ with a unique closed orbit. We show that the Serre functor is given by tensoring with the local cohomology of $\omega_\mathcal{Y}$ at the unique closed orbit. Using this description, we develop analogues of the Matlis and local duality theorems for local rings.

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Ivan Noden. 2026-05-20. Serre functors and local duality for affine quotients. https://arxiv.org/abs/2605.21290

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